The present invention relates to a receiving apparatus that receives a digital broadcast signal that is being broadcast on a tuned channel.
In digital broadcasting, as is publicly known, broadcasting can be performed by a stream in which data for a plurality of programs is multiplexed. That is, it is possible to broadcast a plurality of programs on one physical channel. Here, one physical channel means a channel that corresponds to a frequency band of a carrier wave used for program broadcast. With a digital broadcast, because a plurality of programs may be broadcast on one physical channel, it is necessary to decide the channel on which each program is broadcast. Thus, one or a plurality of virtual channels are assigned to a physical channel. Also, by assigning sub-channels, a virtual channel can be used as a plurality of channels that broadcast a program. For example, if a physical channel to which two virtual channel numbers “10” and “11” has been assigned, when broadcasting two programs, by using “10” as the channel number where one of the programs is being broadcast and using “11” as the channel number where the other program is being broadcast, it is possible to decide the channel on which each program is being broadcast. Also, if a physical channel to which one virtual channel number “20” has been assigned, when broadcasting two programs, by using sub-channel numbers “1” and “2”, and using “20-1” as the channel number where one of the programs is being broadcast and using “20-2” as the channel number where the other program is being broadcast, it is possible to decide the channel on which each program is being broadcast. A user tunes a channel with a virtual channel or a virtual channel plus sub-channel.
Also, the digital broadcast receiving apparatus, at an appropriate time, detects whether or not each receivable physical channel is a channel on which a program is being broadcast, and performs a channel search in which, for each physical channel on which a program is being broadcast, for each program being broadcast on that physical channel, the virtual channels or the virtual channel plus sub-channel being used for program broadcast is registered in an all-channel table. The receiving apparatus, prevents tuning of a channel on which a program is not being broadcast by switching the channel (the virtual channel, or the virtual channel plus sub-channel) based on the all-channel table registration contents when a channel up/down operation has been performed by the user.
On the other hand, with a digital broadcast, as disclosed in JP 2002-354353A and JP 2004-186975A, the number of programs being broadcast on a physical channel changes dynamically. Thus, circumstances arise in which after the previous channel search, a channel on which program broadcast has been stopped (i.e., a channel on which a program is not being broadcast) is tuned, or in which after the previous channel search, a channel on which program broadcast has begun cannot be tuned. Accordingly, in the conventional technology, the all-channel table is updated by performing a channel search when the apparatus main body is powered on or the like.
Also, in JP 2002-354353A, it is proposed to detect the channel configuration of a physical channel on which a program being received is being broadcast, and when there has been a change in the channel configuration, to output an OSD image that indicates that fact. The channel configuration is the configuration of virtual channels or virtual plus sub-channels being used for program broadcast in that physical channel. Also, in JP2004-186975A, it is proposed to, when there is a difference in the channels on which a program is being broadcast detected by a channel search and the channels on which a program is being broadcast detected by a previous channel search, inform the user of this difference, and have the user perform an operation to update the all-channel table.
Also, with a digital broadcast, because a plurality of programs can be broadcast on one physical channel, the total number of programs being broadcast is large, and operations to tune the program that the user will view is troublesome. Accordingly, it is conceived to provide a favorite channel table, in which the user registers a channel (a virtual channel or a virtual channel plus sub-channel) on which a program they like is being broadcast, and when a channel up/down operation is performed by the user, switch channels based on the registered content of the favorite channel table, not the all-channel table.
However, when a configuration is adopted in which when it has been detected that a program is not being broadcast on a channel that is registered in the favorite channel table, this channel is deleted from the favorite channel table, a channel that the user registered in the favorite channel table is deleted from the favorite channel table without the user's knowledge. In this case, when the user checks the registered content of the favorite channel table, the user notices that the channel they registered is not registered in the favorite channel table. As a result, there is the problem that the user is made to feel uneasy that the receiving apparatus main body may be broken, confusing the user. Also, when the program broadcast stoppage on the channel deleted from the favorite channel table is temporary, there is the problem that it is necessary for the user to again perform the operation that registers the deleted channel in the favorite channel table, increasing the burden on the user, so operability is poor.
Also, when a configuration is adopted in which when it has been detected that a program is not being broadcast on a channel that is registered in the favorite channel table, this channel is not deleted from the favorite channel table, when the user tunes this channel, video and audio are not output. At this time, there is the problem that the user erroneously thinks that they made a mistake in the registration operation of the channel to the favorite channel table, and as a result the user is confused.